Electrodepositing-cell.



UNITED STATES PATENT Prion.

MAROEL PERREUR-LLOYD, OF LONDON, ENGLAND, ASSIGNOR TO THE ELECTRICALCOPPER COMPANY, LIMITED, OF SAME PLACE.

ELECTRODEPO'SITING-CELL.

SPECIFICATION forming part of Letters Patent No. 636,212, dated October31, 1899. Application filed December 28, 1897. fierial No. 663,833. (Nomodel.)

- date the 2d day of February, 1897,) of which the following is aspecification.

This invention relates to apparatus for the electrodeposition of copperand othermetals upon rotary cathodes wherein an organic membranoussubstance is used in contact with the cathode for the purpose ofinsuring a dense homogeneous deposit.

According to this invention the organic membranous substances which areknown as and are called herein impregnators con sist of animalmembranessuch as skins, intestines, and bladders-which have had removedfrom them any adherent or excessive fatty or fleshy matters and whichhave pref erably been subjected for a few hours to the action of alime-bath. The membranous substances which are at present employed aresuch as are naturally or artificially charged with fatty or adhesiveinsulating matters which coat any projection from the surface of therotary cathode practically in the same manner as the faces of type arecoated in rotary typography. This coating with an adhesive insulator isonly temporary and is removed by the combined actions of the electrolyteand of theimpregnators. As hereinbefore stated,I,0n the contrary, am.careful to deprive the membranous su bstances which I employ as myimpregnators of all excess of fatty and fleshy matters in practicallythe same way and to the same extent as sheep and calf skins aresimilarly deprived in the manufacture of parchment and vellum. If myimpregnators so prepared are microscopically examined, it will be foundthat they consist of a tangled mass of minute fibers and filaments,which are chiefly composed of fibrin, gelatin, and albumen. If they areplunged in water at or below a temperature of about Fahrenheit, thesefibers and filaments remain unaltered and their mass is found to be,While unaltered in construction, soft and yielding to the touch.

I may employ the impregnators in this condition, or I may further treatthem to render them more insoluble in the event of the temperature ofthe bath accidentally rising above 60 Fahrenheit, as, owing to thedensity of the electric current andthe resistance of the electrolyte, itmay do in warm weather. For this purpose the membranous substance may beimmersed for a short time in a bath containing from two and one-half tofive per cent. of po tassium bichromate in water and be thereaftersolarized or exposed to light andwashed, as in certain photographicprocesses. Other methods maybe employed for rendering the impregnatorsmore insoluble in a similarmanner, as is well understood. In use theimpregnators are simply arranged in light contact upon the surface ofthe cathode, so that the least roughness or asperity thereon seizes someof the minute fibers and filaments, with whichit becomes so covered asto prevent or retard the further deposition of metal thereon. In themeantime the deposition proceeds upon the surface surrounding theasperities, and the former will thus become relatively higher andhigher, while the fibers are removed by the wash of the electrolyte andthe contact of the impregnators. As the relative heights of theasperitiesdiminish they will take up or be covered by fewer and fewer ofthe fibers until finally, with the, equality in height with thesurrounding surfaces, no more fibers are seized and the last of them areWashed off or removed, whereupon the deposition becomes,

again uniform.

It has been found that when organicimpregnators are used,as hereinbeforedescribed,and particularly when they have not been treated with a viewto render them more insoluble, it is necessary to maintain the bath inthe working vat at a temperature which should not exceed 60 Fahrenheit.If this temperature should be exceeded, a solvent action on theimpregnators results, which not only wastes them, but. fouls theelectrolyte. To avoid this result, I adopt precautions to insure thatthe bath is kept sufficiently 0001. This may be accomplished by a systemof circulation and cooling which may be accompanied by the insuffiationof air and filtration. The insufflation of air not only oxidizes anyorganic matter in the bath, but tends also to precipitate any iron theremay be in solution. The oxidation may be aided by the addition ofoxidizing agents. It is also then necessary to provide means for gettingrid of any of the organic matter which may come into solution orsuspension.

Having now particularly described and ascertained the nature of my saidinvention and in what manner the same is to be performed, I declare thatwhat I claim is 1. In an electrodepositing-cell, the combination with ananode and a rotary cathode, of a normal animal skin or membrane arrangedin light contact with the rotary cathode and freed from all matterswhich can become soluble or adhesive at or below 60 Fahrenheit.

2. In an electrodepositing-cell, the combination of an anode, a rotarycathode, and an impregnator arranged in light contact with the rotarycathode, said impregnator being composed of normal animal skins ormembranes freed from excess of fatty matters and from matters Which areor can become soluble or adhesive at or below 60 Fahrenheit.

MAROEL PERREUR-LLOYD.

\Vitnesses:

WILLIAM E.- HEYS, ARTHUR MILLVVARD.

